Ecthyma gangrenosum is a necrotic skin lesion associated with sepsis or other systemic infectious disease.

Clinical picture:

(1) The patient is typically immunocompromised with a systemic infection.

(2) A circumscribed area of skin develops that is initially erythematous but which eventually turns black and necrotic.

(3) The area ulcerates.

(4) If the patient survives then a scar develops.


The classic pathogen for ecthyma gangrenosum is Pseudomonas aeruginosa.


Other organisms capable of causing the syndrome include:

(1) Staphylococcus aureus or other species

(2) Streptococcus pyogenes

(3) E. coli and other Enterobacteriaceae (Citrobacter, Klebsiella, etc)

(4) Aeromonas

(5) Chromobacterium

(6) Corynebacterium diphtheriae

(7) Neisseria gonorrhoeae

(8) Yersinia pestis

(9) fungi (Aspergillus, Curvilaria, other)

(10) Candida albicans

(11) Herpes simplex virus (HSV)


Culture or molecular studies are needed to diagnose the pathogen. Multiple pathogens may be involved. Culture is also useful in adjusting therapy.

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